{"id":17192,"date":"2022-08-12T02:06:43","date_gmt":"2022-08-12T02:06:43","guid":{"rendered":"http:\/\/www.alalloycasting.com\/?p=17192"},"modified":"2022-08-25T02:32:40","modified_gmt":"2022-08-25T02:32:40","slug":"porous-ceramic-filter-slurry","status":"publish","type":"post","link":"https:\/\/www.alalloycasting.com\/tr\/porous-ceramic-filter-slurry\/","title":{"rendered":"g\u00f6zenekli seramik filtre \u00e7amuru"},"content":{"rendered":"

g\u00f6zenekli seramik filtre<\/a> \u00c7amur emdirme i\u015flemi, \u00e7amur i\u00e7in kat\u0131 gereklilikler i\u00e7erir. Bu makale, s\u00f6z konusu emdirme s\u00fcrecini a\u00e7\u0131klamaktad\u0131r.<\/p>\n

organik (polimer) k\u00f6p\u00fck emdirme<\/p>\n

Organik k\u00f6p\u00fck dald\u0131rma i\u015flemi, 1963 y\u0131l\u0131nda Schwartzwalder taraf\u0131ndan icat edilmi\u015ftir. Bu y\u00f6ntem, seramik hamurunu organik k\u00f6p\u00fckle emprenye etmek ve kurutulduktan sonra organik k\u00f6p\u00fc\u011f\u00fc yakarak \u00fcr\u00fcn\u00fc elde etmeyi i\u00e7erir. Kaliteli \u00e7amur, organik k\u00f6p\u00fck a\u011f\u0131n\u0131n \u00fczerine d\u00fczg\u00fcn bir \u015fekilde kaplan\u0131r ve organik k\u00f6p\u00fc\u011f\u00fcn yak\u0131lmas\u0131ndan sonra a\u011f tipi g\u00f6zenekler elde edilir.<\/p>\n

Nihai \u00fcr\u00fcn\u00fcn g\u00f6zenek boyutu esas olarak organik k\u00f6p\u00fc\u011f\u00fcn g\u00f6zenek boyutuna ba\u011fl\u0131d\u0131r ve ayr\u0131ca organik k\u00f6p\u00fck \u00fczerindeki bulamac\u0131n kaplama kal\u0131nl\u0131\u011f\u0131yla da belirli bir ili\u015fki i\u00e7indedir; ancak a\u011f yap\u0131l\u0131 g\u00f6zenekli cismin g\u00f6zenek yap\u0131s\u0131, organik k\u00f6p\u00fck matrisinin g\u00f6zenek yap\u0131s\u0131 ile neredeyse ayn\u0131d\u0131r. G\u00f6zeneklerin \u00fc\u00e7 boyutlu a\u011f iskelet yap\u0131s\u0131. Bu i\u015flemin g\u00f6zenek olu\u015fturma prensibi \u015eekil 1-1'de g\u00f6sterilmi\u015ftir.<\/p>\n

Bu \u00f6zel yap\u0131, filtre malzemesi olarak \u00f6nemli avantajlar sa\u011flar: (1) Ak\u0131\u015fkan i\u00e7inden ge\u00e7ti\u011finde bas\u0131n\u00e7 kayb\u0131 azd\u0131r. (2) Geni\u015f y\u00fczey alan\u0131 ve y\u00fcksek ak\u0131\u015fkan temas verimlili\u011fi. (3) Hafiftir. Geleneksel olarak kullan\u0131lan seramik par\u00e7ac\u0131kl\u0131 sinterlenmi\u015f g\u00f6vde ve cam elyaf kuma\u015fla kar\u015f\u0131la\u015ft\u0131r\u0131ld\u0131\u011f\u0131nda, bu t\u00fcr g\u00f6zenekli seramik filtreler ak\u0131\u015fkan filtrasyonu, \u00f6zellikle de erimi\u015f metal filtrasyonu i\u00e7in kullan\u0131l\u0131r.<\/p>\n

(1) Seramik \u00e7amurunun serbest\u00e7e n\u00fcfuz edebilmesini ve birbirine yap\u0131\u015fabilmesini sa\u011flamak \u00fczere a\u00e7\u0131k g\u00f6zenekli bir malzeme olmal\u0131d\u0131r; b\u00f6ylece pi\u015firme i\u015fleminden sonra g\u00f6zenekli, \u00fc\u00e7 boyutlu bir a\u011f iskeleti olu\u015fabilir;<\/p>\n

(2) Seramik \u00e7amurunu s\u0131k\u0131ca tutabilecek belirli bir derecede hidrofilikli\u011fe sahip olmal\u0131d\u0131r<\/p>\n

(3) Fazla \u00e7amurun h\u0131zla geri toparlan\u0131p eski \u015fekline kavu\u015fmas\u0131n\u0131 sa\u011flayacak yeterli esneklik bulunmal\u0131d\u0131r;<\/p>\n

(4) Seramiklerin pi\u015firme s\u0131cakl\u0131\u011f\u0131n\u0131n alt\u0131nda buharla\u015f\u0131r ve seramikleri kirletmez.<\/p>\n

\"g\u00f6zenekli
g\u00f6zenekli seramik filtre \u00e7amuru<\/figcaption><\/figure>\n

Seramik tozu, \u00fcr\u00fcn\u00fcn farkl\u0131 kullan\u0131m ama\u00e7lar\u0131na g\u00f6re se\u00e7ilir. g\u00f6zenekli seramik filtre<\/a> geli\u015ftirilen \u00e7amur halindeki malzeme. \u00d6rne\u011fin, al\u00fcminyum, bak\u0131r, \u00e7inko, kalay ve di\u011fer d\u00fc\u015f\u00fck erime noktal\u0131 ala\u015f\u0131mlar gibi demir d\u0131\u015f\u0131 metalleri filtrelemek i\u00e7in genellikle kordierit, al\u00fcmina, Al\u2082O\u2083 ve Al\u2082O\u2083CrO\u2083 serisi malzemeler se\u00e7ilir; demir i\u00e7eren metallerin ve ala\u015f\u0131mlar\u0131n\u0131n eritilmesinde ise kimyasal aktivite ve d\u00f6k\u00fcm s\u0131cakl\u0131\u011f\u0131n\u0131n daha y\u00fcksek olmas\u0131 nedeniyle.<\/p>\n

Y\u00fcksek s\u0131cakl\u0131k filtresi olarak silikon karb\u00fcr\u00fcn kullan\u0131m\u0131; erimi\u015f \u00e7eli\u011fi filtrelemek i\u00e7in k\u0131smen stabilize edilmi\u015f ZrO\u2082-Al\u2082O\u2083 serisi malzemelerin ve magnezyum-al\u00fcminyum serisi filtre malzemelerinin kullan\u0131lmas\u0131, erimi\u015f \u00e7elikteki kal\u0131nt\u0131lar\u0131n i\u00e7eri\u011fini etkili bir \u015fekilde azaltabilir; seramik olarak kordierit-mullit kompozitinin kullan\u0131lmas\u0131, filtrenin dizel egzoz partik\u00fcllerini s\u00fczmesini sa\u011flar. Sonu\u00e7 olarak, uygun seramik tozlar\u0131n\u0131n se\u00e7imi, y\u00fcksek performansl\u0131 ve pratik g\u00f6zenekli seramik filtre malzemelerinin haz\u0131rlanmas\u0131 i\u00e7in \u00e7ok \u00f6nemlidir.<\/p>\n

\u00c7amur, esas olarak seramik tozu, \u00e7\u00f6z\u00fcc\u00fc ve katk\u0131 maddelerinden olu\u015fur. Genellikle \u00e7\u00f6z\u00fcc\u00fc olarak su kullan\u0131l\u0131r, ancak etanol gibi organik \u00e7\u00f6z\u00fcc\u00fcler de kullan\u0131lmaktad\u0131r. Genel seramik bulamac\u0131n\u0131n \u00f6zelliklerine ek olarak, bulamac\u0131n m\u00fcmk\u00fcn oldu\u011funca y\u00fcksek bir kat\u0131 madde i\u00e7eri\u011fine (su i\u00e7eri\u011fi genellikle ~40, bulamac\u0131n \u00f6zg\u00fcl a\u011f\u0131rl\u0131\u011f\u0131 18~2,2 g\/cm\u00b3't\u00fcr) ve daha iyi tiksotropiye sahip olmas\u0131 gerekir. Y\u00fcksek performansl\u0131 \u00e7amur, sadece kal\u0131plama i\u00e7in faydal\u0131 olmakla kalmaz, ayn\u0131 zamanda \u00fcr\u00fcnlerin performans\u0131n\u0131 sa\u011flamada da \u00f6nemli bir rol oynar. Ayn\u0131 zamanda, dald\u0131rma kal\u0131plamaya daha uygun bir \u00e7amur elde etmek i\u00e7in belirli miktarda katk\u0131 maddesi eklenmelidir. Katk\u0131 maddeleri genellikle a\u015fa\u011f\u0131dakilerden olu\u015fur:<\/p>\n

(1) Ba\u011flay\u0131c\u0131. A\u011f haz\u0131rlamak \u00fczere bulama\u00e7 i\u00e7ine bir ba\u011flay\u0131c\u0131 ilave edilmesi g\u00f6zenekli seramik filtre<\/a> \u00c7amur, kurutma sonras\u0131nda ham g\u00f6vdenin mukavemetini art\u0131rmaya yard\u0131mc\u0131 olmakla kalmaz, ayn\u0131 zamanda organik madde giderme i\u015flemi s\u0131ras\u0131nda ham g\u00f6vdenin \u00e7\u00f6kmesini de \u00f6nler; b\u00f6ylece nihai sinterlenmi\u015f g\u00f6vdenin yeterli mekanik mukavemete sahip olmas\u0131n\u0131 sa\u011flar. Ba\u011flay\u0131c\u0131lar, inorganik ba\u011flay\u0131c\u0131lar ve organik ba\u011flay\u0131c\u0131lar olarak ikiye ayr\u0131l\u0131r. Yayg\u0131n olarak kullan\u0131lan inorganik ba\u011flay\u0131c\u0131lar aras\u0131nda potasyum, sodyum silikat, borat, fosfat, al\u00fcminyum hidroksit sol ve silika sol bulunur. Ba\u011flay\u0131c\u0131n\u0131n t\u00fcr\u00fc ve \u00f6zellikleri, \u00fcr\u00fcn\u00fcn performans\u0131 \u00fczerinde b\u00fcy\u00fck bir etkiye sahiptir. A\u011f\u0131n performans\u0131n\u0131 iyile\u015ftirmek i\u00e7in uygun ba\u011flay\u0131c\u0131y\u0131 se\u00e7mek \u00e7ok \u00f6nemlidir. \u00d6rne\u011fin, g\u00f6zenekli al\u00fcmina, ba\u011flay\u0131c\u0131 olarak al\u00fcminyum hidroksit jeli kullan\u0131larak haz\u0131rlan\u0131r; bu, filtrenin erimi\u015f al\u00fcminyuma kar\u015f\u0131 korozyon direncini b\u00fcy\u00fck \u00f6l\u00e7\u00fcde art\u0131r\u0131r.<\/p>\n

(2) Da\u011f\u0131t\u0131c\u0131. Bulama\u00e7\u0131n kat\u0131 madde i\u00e7eri\u011fini art\u0131rmak i\u00e7in, hem su bazl\u0131 hem de su bazl\u0131 olmayan sistemlere da\u011f\u0131t\u0131c\u0131lar eklenmelidir. Dispersanlar, \u00e7amurun stabilitesini art\u0131rabilir, par\u00e7ac\u0131klar\u0131n yeniden topaklanmas\u0131n\u0131 \u00f6nleyebilir ve b\u00f6ylece \u00e7amurun kat\u0131 madde i\u00e7eri\u011fini art\u0131rabilir. Ancak, farkl\u0131 toz sistemleri i\u00e7in dispersanlar\u0131n etkisinin genellikle farkl\u0131 oldu\u011fu unutulmamal\u0131d\u0131r. Al2O3'\u00fcn su bazl\u0131 sistemi i\u00e7in, yaln\u0131zca 25wt% poliamin iyi bir da\u011f\u0131t\u0131m etkisine sahiptir; SiC'nin su bazl\u0131 sistemi i\u00e7in ise PEI (polietilenimin) ideal bir da\u011f\u0131t\u0131c\u0131d\u0131r. K\u0131sacas\u0131, uygun dispersan\u0131n se\u00e7ilmesi, bulamac\u0131n kat\u0131 madde i\u00e7eri\u011fini art\u0131rman\u0131n \u00f6nemli bir yoludur.<\/p>\n

(3) Reoloji ajan\u0131. Bu i\u015flemin kal\u0131plama \u00f6zelliklerine g\u00f6re, bulamac\u0131n yaln\u0131zca belirli bir ak\u0131\u015fkanl\u0131\u011fa sahip olmas\u0131 de\u011fil, ayn\u0131 zamanda iyi bir tiksotropiye de sahip olmas\u0131 gerekmektedir; yani bulamac\u0131n hareketsizken kat\u0131la\u015fm\u0131\u015f durumda olmas\u0131, ancak d\u0131\u015f kuvvetin etkisiyle ak\u0131\u015fkanl\u0131\u011f\u0131n\u0131 geri kazanmas\u0131 gerekmektedir. \u00c7amurun ak\u0131\u015f \u00f6zellikleri, emprenye i\u015flemi s\u0131ras\u0131nda \u00e7amurun organik k\u00f6p\u00fc\u011fe n\u00fcfuz etmesini ve k\u00f6p\u00fck a\u011f\u0131n\u0131n h\u00fccre duvarlar\u0131na e\u015fit bir \u015fekilde kaplanmas\u0131n\u0131 sa\u011flar. Sulu kar\u0131\u015f\u0131m\u0131n tiksotropisi, kar\u0131\u015f\u0131m\u0131n dald\u0131r\u0131lmas\u0131 ve fazla kar\u0131\u015f\u0131m\u0131n s\u0131k\u0131\u015ft\u0131r\u0131lmas\u0131 s\u0131ras\u0131nda kesme kuvveti alt\u0131nda viskozitenin azalmas\u0131n\u0131, ak\u0131\u015fkanl\u0131\u011f\u0131n\u0131n artmas\u0131n\u0131 sa\u011flar ve bu da kal\u0131plama i\u015flemi i\u00e7in faydal\u0131d\u0131r. Kal\u0131plama i\u015fleminin sonunda, bulamac\u0131n viskozitesi artar ve ak\u0131\u015fkanl\u0131\u011f\u0131 azal\u0131r. Bu, delik duvar\u0131na yap\u0131\u015fan bulamac\u0131n kolayca yuvarlan\u0131p \u015fekillendirilmesini sa\u011flar; b\u00f6ylece bulamac\u0131n ak\u0131\u015f\u0131 nedeniyle ham g\u00f6vdenin ciddi \u015fekilde t\u0131kanmas\u0131ndan kaynaklanan \u00fcr\u00fcn g\u00f6zeneklerinin d\u00fczensizli\u011fi \u00f6nlenir. \u00c7amurun reolojik \u00f6zelliklerini, \u00f6zellikle tiksotropisini iyile\u015ftirmek i\u00e7in eklenen reolojik ajanlar genellikle bentonit, kaolin ve karboksimetil sel\u00fcloz gibi do\u011fal killer (0,1~12w%)d\u0131r.<\/p>\n

(4) Y\u00fczey aktif madde. Seramik bulamac\u0131 su bazl\u0131 bir bulamac\u0131 ise ve organik k\u00f6p\u00fck \u00f6nc\u00fcs\u00fc ile bulama\u00e7 aras\u0131ndaki \u0131slanabilirlik yetersizse, bulamac\u0131n dald\u0131r\u0131lmas\u0131 s\u0131ras\u0131nda k\u00f6p\u00fck yap\u0131s\u0131n\u0131n kesi\u015fti\u011fi k\u0131sma kal\u0131n bir bulama\u00e7 tabakas\u0131 yap\u0131\u015f\u0131r ve ciddi durumlarda bu durum, sinterleme i\u015flemi s\u0131ras\u0131nda ham par\u00e7an\u0131n \u00e7atlamas\u0131na ve g\u00f6zenekli seramik filtre<\/a>r \u00e7amurunun hacmi a\u00e7\u0131k\u00e7a azalm\u0131\u015f, hatta \u00e7\u00f6km\u00fc\u015f durumdad\u0131r. Bu nedenle, bu sorunu \u00e7\u00f6zmek amac\u0131yla genellikle seramik \u00e7amuru ile organik k\u00f6p\u00fck aras\u0131ndaki yap\u0131\u015fmay\u0131 iyile\u015ftirmek i\u00e7in y\u00fczey aktif madde ekleme y\u00f6ntemi kullan\u0131l\u0131r; \u00f6rne\u011fin PEI (polietilenimin) ekleme gibi.<\/p>\n

(5) K\u00f6p\u00fck \u00f6nleyici. Dald\u0131rma ve fazla hamurun ekstr\u00fczyonu s\u0131ras\u0131nda hamurun k\u00f6p\u00fcrmesini ve bunun \u00fcr\u00fcn\u00fcn performans\u0131n\u0131 etkilemesini \u00f6nlemek i\u00e7in, genellikle d\u00fc\u015f\u00fck molek\u00fcler a\u011f\u0131rl\u0131kl\u0131 alkol veya silikon gibi bir k\u00f6p\u00fck \u00f6nleyici maddenin eklenmesi gerekir. Organik k\u00f6p\u00fck, bulamaca emdirilmeden \u00f6nce havay\u0131 \u00e7\u0131karmak i\u00e7in tekrar tekrar s\u0131k\u0131lmal\u0131 ve ard\u0131ndan bulamaca emdirilmelidir. Y\u00f6ntemler aras\u0131nda atmosferik bas\u0131n\u00e7l\u0131 adsorpsiyon y\u00f6ntemi, vakumlu adsorpsiyon y\u00f6ntemi, makine ile ak\u00e7aa\u011fa\u00e7 yuvarlama y\u00f6ntemi ve manuel ovma y\u00f6ntemi bulunmaktad\u0131r. Emdirme i\u00e7in hangi y\u00f6ntem kullan\u0131l\u0131rsa kullan\u0131ls\u0131n, bulamac\u0131n organik k\u00f6p\u00fc\u011f\u00fcn \u00fczerine tamamen kaplanmas\u0131 gerekir. Organik k\u00f6p\u00fck bulamac\u0131yla emdirildikten sonra, fazla bulamac\u0131n uzakla\u015ft\u0131r\u0131lmas\u0131 gerekir. Bu ad\u0131m\u0131n anahtar\u0131, ekstr\u00fczyon kuvvetinin homojenli\u011fidir. G\u00f6zenek t\u0131kanmas\u0131n\u0131 \u00f6nlemek i\u00e7in fazla bulamac\u0131n uzakla\u015ft\u0131r\u0131lmas\u0131 ve bulamac\u0131n a\u011f g\u00f6zenek duvar\u0131nda e\u015fit bir \u015fekilde da\u011f\u0131lmas\u0131n\u0131n sa\u011flanmas\u0131 gerekir. Olu\u015fan ham g\u00f6vdenin y\u0131\u011f\u0131n yo\u011funlu\u011fu 0,4~0,8 g\/cm\u00b3 aral\u0131\u011f\u0131nda olmal\u0131d\u0131r. B\u00fcy\u00fck \u00f6l\u00e7ekli \u00fcretim, santrif\u00fcjler veya haddeleme makineleri gibi ekipmanlarla ger\u00e7ekle\u015ftirilmelidir.<\/p>\n

Fazla \u00e7amurun ekstr\u00fczyon yoluyla elde edilen ye\u015fil g\u00f6vde kurutulmal\u0131d\u0131r; bu i\u015flem g\u00f6lgede, f\u0131r\u0131nda veya mikrodalga f\u0131r\u0131nda ger\u00e7ekle\u015ftirilebilir. Nem i\u00e7eri\u011fi %1,0'\u0131n alt\u0131na d\u00fc\u015ft\u00fc\u011f\u00fcnde pi\u015firilebilir. \u00dcretim d\u00f6ng\u00fcs\u00fcn\u00fc k\u0131saltmak i\u00e7in genellikle makul bir kurutma sistemi olu\u015fturulmas\u0131 gerekir.
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